NSF Lube is a fast-growing chain of oil-change stores. The following data are available for last years services. NSF Lube performed 471,200 oil changes last year. It had budgeted 433,600 oil changes, averaging 10 minutes each. Standard variable labor and support costs per oil change were as follows. Direct oil specialist services: 10 minutes at $30 per hour $ 5.00 Variable support staff and overhead: 7.5 minutes at $20 per hour 2.50 Fixed overhead costs: Annual budget $1,037,600 Fixed overhead is applied at the rate of $2.40 per oil change. Actual oil change costs